Ankle joint for artificial limbs



C. B. WINN ANKLE JOINT FOR ARTIFICIAL LIMBS Dec. 1, 1925- Filed Dec. 29.192

A7 A Aw 1. EH 2% Patented Dec. 1, 1925.

uuirso STATES onnsrna B. WINN, or BUFFALO, NEW YORK.

ANKLE JOINT FOR ARTIFICIAL LIMBS.

Application filed December 29, 1924.

To all whom it may concern:

Be it known that I, Crrnstrnn B. VINN, a citizen of the United States,residing in Buffalo, in the county of Erie and State of New York, haveinvented new and useful Improvements in Ankle Joints for ArtificialLimbs, of which the following is a specification.

The invention relates generally to artificial limbs but moreparticularly to improvements in the ankle-joints or journals of suchlimbs.

Its chief object is to provide ,a simple and substantial joint orjournal of this character with a view of gaining greater firmness andsecurity in retaining the leg and foot sections in alinement and inproper working relation. 1

A further object of the invention is the provision of an ankle-jointwhich is reliably held against lateral or endwise displacement and soconstructed as to reduce the wear on the parts thereof to a minimum.

In the accompanying drawings:Figure 1 is a fragmentary side elevation ofan artificial leg embodying my invention. Figure 2 is a centrallongitudinal section thereof. Figure 3 is an enlarged transverse section011 line 3-3, Fig. 2. Figure 4: is a top plan view of that part of thejoint contained in the foot-section of the leg. Figure 5 is a detachedperspective view of the complementary parts of the joint. Figure 6 is afragmentary perspective View of a modified form of the joint. Figure 7is a transverse section, partly in elevation, showing anothermodification of the improvement. Figure 8 is a perspective View of thejoint of the last-mentioned modification.

Similar characters of reference indicate corresponding parts throughoutthe several views.

The artificial limb illustrated in the drawings, comprises a foot 10 anda leg or shinsection 11, the foot having an elastic heelbloclr 12 and acushion 13 disposed in front of the ankle-joint between the opposingfaces of the foot and leg member.

In the preferred construction of the improved ankle-joint or ournalshown in Figs. l a"), inclusive, the same comprises a transverse sleeveor bearing member 14 having substantially semi-cylindrical concavehearing surfaces 15 at its opposite ends and a convex bearing surface 16intermediate the Serial No. 758,593.

latter. The upper side of this sleeve is seated in a recess or cavityl?in the bottom of the leg member 11, while the lower convex portion 16thereof engages a complementary concave bearing seat or surface 18formed in the opposing upper portion of the foot 10. Said sleeve may besecured to the leg member by an upright bolt 19 or other suitablefastening. A hollow journal pin 20 is journaled in the central or convexbearing portion of the sleeve and fastened to the foot by a bolt 21passing through a transverse slot 22 in the bottom of the sleeve.

The upper portion of the foot 10 is provided on opposite sides of itsconcave bearing surface 18 with convex bearings or trunnions 23 uponwhich the companion concave bearings 15 of the sleeve 14 rest, as shownin Figs. 3 and 4:. Said convex bearings 23 may be carried by attachingplates or brackets 2a secured to opposite sides of the foot by screws 25or other appropriate fastenings. The bottom portions of these convexbearings are somewhat larger in diameter than their upper portions, theresulting upwardly-facing shoulders 26 constituting stops with which theopposingends of the concave sleeve-bearings 15 are adapted to abut forlimiting the swinging action of the leg relative to the foot. Thebottoms of the convex bearings 23 are preferably seated in the endportions of the concave foot-bearing 18. As shown in Fig. 3, the ends ofthe convex journal bearing 16 abut against the opposing inner ends ofthe corresponding foot-bearings 24.

For the purpose of attaining additional strength and'security, ahorizontal shaft or bolt 27 may be extended through the hollowjournal-pin 20 and alining openings 28 in the convex journal bearings23. The latter may' be faced with leather 29 or similar material to forma silent joint.

By constructing the ankle-joint with alternating complemental convex orconcave bearings, with a comparatively deep center seating of the convexportion 16 of the journal, the bearings are not only protected, butlateral or endwise displacement of the parts is effectually prevented,thereby producing a firm, extensive and rigid joint capable ofwithstanding the severe strains which are imposed upon it. Furthermore,by the interlocking arrangement of the con vex and concave bearings, thefoot is held against moving sidewise or twisting, with the result thatthe leg and foot sections are maintained in alinement and in properworking relation.

If desired, instead of making the convex bearings 24 separate ordetachable from the foot 10, they may be formed in one piece with thewooden portion thereof, as shown at in Fig. ,6.

As a further modification of the invention, the arrangement of thecon-vex and concave bearings may be reversed, as illustrated in Figs. '7and 8. Inthi-s case, the journal sleeve 31 is provided at Opposite endsWith convex bearing surfaces 32 and in its center with a concave bearingsurface 33, the convex bearing surfaeesengaging complementary concavesets 34 formed in theopposing upper portion'ofj the foot 10, while theconcave bearing surface rests on a, central convex bearing 35 ofthefoot. The journal-sleeve is secured to the leg member 11' by an uprightbolt 36 and its ends are supported in a;nti'f1'ietion or ball bearings37. A horizontal shaft 38 extends through the opposedbearingsand issupported at its ends in. plates 39 fastened to the opposite sides ofthe foot. The outer rings of the anti-friction bearings 37 are pressedinto the ends of the journal-sleeve 31, whilethe inner rings are pressedon the shaft 38, said inner rings being secured to the foot by bolts- 40passing through-alini-ng transverse slots 4-1 in the sleeve and outerbearing ring, respectively. v

The invention is susceptible of other changes, within the scope oftheappended claims, and I do not thereforewish to be limited to theparticular embodiment ofthe invention herein shown and described.

I claim as my invention i I 1. An ankleejoint for artificial limbs,comprising a journal carried by the "legmember and having both convexand concave bearing surfaces, and opposed com-plementa'l concave andconvex bearing surfaces applied to the foot.

:2. An ankle-joint for artificial limbs, comprising a journal carried bythe legmember and having alternately arranged convex and concavebearings, and opposed complemental concave and convex bearings appliedto the foot, the ends of the convex journal-bearings abutting againstthe opposing ends of the corresponding foot-bearings.

3. An ankle-joint for artificial. limbs, comprising a journal carried bythe legmember and having both convex and con cave bearing portions, apin journaledin the convex bearing portions, means for connectiiig saidjournal andsaid pin to the leg member and foot, respectively, andopposed complemental concave and convex bearings applied to the foot. Ip

l. An ankle-joint for artificial limbs, comprising tijournal carried bythe leg member and having both convex and concave bearing surfaces,opposed compleinental concave and convex bearing surfaces applied to thefoot, and a transverse shaft extending axially through thejournalbearings and the foot-bearings; v

5. An ankle-joint for artificial limbs, comprising a journal carried bythe legmember and having a central convex hearing and concave endbearings, and hearing trunnions applied to opposite sides of the footfor engagement with the concave bearin 'sof said journal, the foothaving a concave bearing between said trunnions for receiving the convexjournal-bearings.

6. An ankle-journal, comprising a sleeve having alternately-disposedconcave and convex bearing surfaces and means for connecting the sleeveto; the leg and foot mem bers of an artificial limb.

7. An ankle-journal, comprising a sleeve having alternately-disposedconcave and convex bearing surfaces, and fastening bolts applied tothoseportion's of the sleeve con taining said convex bearing-surfacesand extending in opposite directions therefrom.

CHESTER B. WINK.

